For example, in publicly known game machines such as slot game machines, a correspondence relationship between winning combinations and dividend values (odds, a number of dividends or dividend amount) is preset and when any winning combination is achieved, a dividend is given to a player according to the dividend value set for this winning combination. In these game machines, the dividend value is generally varied according to a probability of achievement in a winning combination. Also in publicly known game machines, when a predetermined condition is established in a game, an arrangement order of odds is shuffled by using random numbers so that a correspondence relationship between winning combinations and odds is changed (for example, see Patent Document 1).
Further, in publicly known game machines, when symbols to be arranged on a predetermined area on a game screen in a predetermined positional relationship (matrix pattern as one example) is drawn randomly from predetermined types of symbols and then the types and the arrangement of these symbols achieve predetermined winning combinations, winning is determined In some of such a kind of game machines, not only normal symbols are available as one type of symbols in a determination of success or failure of a winning condition; also, common symbols that are available as two or more types (typically all types) of normal symbols in the determination of the success or failure of the winning condition are included in symbol candidates to be selected. When a predetermined condition is established, the common symbols are arranged on a predetermined area and the probability of establishment of the winning condition is heightened (for example, see Patent Document 2).
Further, in publicly known game machines, when symbols to be arranged on a predetermined area on a game screen in a predetermined positional relationship (a matrix pattern as one example) is drawn randomly from predetermined types of symbols and the same type of symbols whose number is necessary for winning are aligned on a predetermined winning line, a determination is made that a winning combination as a winning condition is achieved. In some of this type of game machines, when a winning combination or a winning condition is about to be established, but winning is narrowly missed (e.g., a case where only one different type of symbol is mixed on a winning line), the user's expectation for winning is heightened by additionally giving a drawing chance (for example, see Patent Document 3).
Patent Document 1: Japanese Patent Application Laid-Open No. 2004-033615
Patent Document 2: Japanese Patent Application Laid-Open No. 2004-173950
Patent Document 3: Japanese Patent Application Laid-Open No. 2005-312481